CMMG Banshee MK4 5.7x28mm 5in Pistol, 32rd

The CMMG Banshee MK4 is an AR-platform pistol chambered in 5.7x28mm with a 5-inch barrel. Built on CMMG’s Mk4 AR15 platform, it uses standard AR15 lower receiver geometry and is compatible with CMMG’s 5.7x28mm conversion magazines. The design employs a radial delayed blowback operating system in a semi-automatic configuration to deliver controlled cycling with reduced perceived recoil. Compact, optics-ready, and outfitted with ambidextrous controls, this configuration is suited to close-quarters applications and users who prioritize maneuverability.

Key Specifications

• The caliber is 5.7 x 28 mm.
• The barrel length is 5 inches.
• The action uses Radial Delayed Blowback in a semi-automatic configuration.
• The magazine capacity is 32 rounds using CMMG 5.7x28mm magazines.
• The barrel material is 4140CM SBN with an MT contour.
• The rifling twist rate is 1:9.
• The muzzle device is a CMMG ZEROED Linear Comp and the muzzle is threaded 1/2 x 28.
• The upper is billet 6061 T6 aluminum and the lower is Mk4 forged 7075 T6 aluminum.
• The handguard is a CMMG EML4 M-LOK and the finish is Cerakote.
• The pistol ships with a CMMG RipBrace, ambidextrous ZEROED controls, and a ZEROED drop-in single-stage trigger.

Compact and thoughtfully specified, the Banshee MK4 delivers a balance of controllability and capability in a small package. Its AR15-based platform, optics-ready upper, ambidextrous controls, and 32-round magazine make it a practical choice for shooters seeking a high-performance, easy-to-handle 5.7x28mm pistol configuration.

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